Pierre Massat is sharing his experience in building a guitar multi-effect on his blog. The project is based on a pedal built hooked up to an Arduino Uno and a PC running Pure Data.

In the blog you’ll find posts about :

• How to build a DIY foot controller
• How to set up a computer to process the sound of a guitar in real-time
• How to make simple effects in Pure Data
• How to let the foot controller and Pure Data talk to each other

I really liked the mechanism built with Lego!